condition mean min max ZT0-3 6.66639 6.66639 6.66639 ZT4-7 6.46535 6.46535 6.46535 ZT8-11 4.5634 4.5634 4.5634 ZT12-15 5.3880099999999995 5.3880099999999995 5.3880099999999995 ZT16-19 7.814864999999999 7.814864999999999 7.814864999999999 ZT20-23 7.042845 7.042845 7.042845